population bottlenecks

[Brittain33]

Those that like to linger around Congress 6, 7, 8 decades and die there clinging to power tend to be Democrats and those who tend to wanna get out and move on to other things tend to be Republican

Republicans have a much easier time moving on to lobbying their former colleagues to pass bills to help whichever industry will cut them a check large enough... some Dems do that, but it's not as common nor so widely accepted a career goal.